Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?
Technology Your Rights Online

IDs in Color Copies 413

Slashdot covers the continuing efforts of music and other industries to eliminate digital copying of, well, just about anything. But what about paper copies? What if every color photocopy you made included a unique serial number to trace the page back to the copy machine? What if every color printer, down to the lowliest inkjet, printed an invisible watermark on every page it printed? What if every scanner included a watermark in every scan that was traceable back to the scanner?

Slashdot received a lot of submissions of this Privacy Forum article about ID numbers being "watermarked" (just like digital watermarks) into copies made by any color copy machine. Go ahead and read it; the rest of this story assumes that you've read the link.

This not a secret; I remember a case a few years ago where a Columbia University copier was being used to create counterfeit currency, and the imprinted copies were traced straight back to the machine used to create them (amazingly, Altavista turned up an article about this case). Basically, when color copiers first started getting good, the Treasury started leaning on manufacturers to make their products less useful for counterfeiting. AFAIK, there's no law in effect saying that manufacturers MUST include an anti-counterfeiting features in their devices; but on the other hand, there aren't very many equipment manufacturers, so they're easy to lean on.

So today, any copy you make with any color copier will include a unique serial number. Make sure you don't copy anything that someone might want to trace back to you on a color copier. Maybe this isn't that big a deal; color copiers aren't home appliances.

But now home scanners and inkjets make up a nice copying system for as little $200-300. The Treasury Department has a big program devoted to preventing digital copying, and it looks like one of their main concerns is consumer-grade equipment. The Bureau of Printing and Engraving is even soliciting proposals from vendors which have a system suitable for embedding these watermarks in all output produced by color inkjet printers.

Fighting counterfeiting is fine with me. Thus the systems which "recognize" currency and refuse to scan or print it don't seem like too much of an infringement. But embedding serial numbers in all printer output? Maybe I just have a cynical mind, but I can think of about a hundred reasons this is a bad idea.

This discussion has been archived. No new comments can be posted.

IDs in Color Copies

Comments Filter:
  • by smileyy ( 11535 ) <smileyy@gmail.com> on Wednesday December 08, 1999 @10:15AM (#1474513)

    What they're talking about is a watermark embedded using steganography -- placed into the noise of the image, much like copy protection of digital images can be done by Photoshop (and other programs) now.

  • by finkployd ( 12902 ) on Wednesday December 08, 1999 @10:18AM (#1474515) Homepage
    We just disable this part of the printer/copier/scanner. Time and time again we learn the collegtive intelligence of people who believe in freedom and "fair use" is much higher than the companies trying to stop us.
    Perhaps someday, someone other than ourselves will realize this.


  • ..just crop the watermark out..
    This is encoded in 'background noise' in the image, and is not visable. The algorithm for decoding the watermark is known only to the manufacturers and a few government agencies.

    ..it would be interesting to watch the black market..

    Wrong. This has been around for at least five years. It is not a new thing. It's been an open secret for years, many people even assuming it was an urban legend, and the media ignoring it.
  • by Steve B ( 42864 ) on Wednesday December 08, 1999 @10:20AM (#1474518)
    At one point [Romanian dictator Nicolae Ceausescu's] censors intercepted some anonymous letters addressed to Radio Free Europe, criticizing the Ceausescus' 'personality cult.' In a fit of rage, Ceausescu ordered his security chiefs to get samples of the handwriting of every school child and adult Romanian, so that their handwriting experts could identify who had written the letters.

    Additionally, he wanted every typewriter owned by the state registered with the Securitate, along with a sample of its type.

    --Dr. James McCollum (Is Communism Dead Forever?)
  • by Mechanical_Governor ( 101122 ) on Wednesday December 08, 1999 @10:21AM (#1474520)
    Canon color lasers (800, 1000, 2400, ect.) all have a board that recognizes things like money and postage stamps. If you try and copy any of these it will spit out all black copies, and will continue to do so until a Canon tech is called. (They usualy call the Secret Service)
  • by debrain ( 29228 ) on Wednesday December 08, 1999 @10:23AM (#1474522) Journal
    As with all digital media, a watermark of any nature, unless generated with the most crytpic of methods, can be removed. Applying watermarks to scanned images would be very difficult to keep there, for those that (a) know about the watermark and (b) care about the watermark. Take DVD's and Audio CD's. Making them digital opens them up to mountains of transformations, not the least of which is the removal of copyright encryption (more of a copyright notice, now).

    Paper and print is a whole different story. I would be wary of buying anything that watermarked everything I printed. I use a (granddaddy) AppleWriter II laser printer, and am reluctant to upgrade to a new printer if I am aware of this sort of thing. My big concern is who can read these watermarks, and why would they ever want to. (Other than for legal reasons, but I can't see myself printing threats off my printer.)

    I can see newer laser printers being able to do this sort of thing, but I cannot see why a printer company would risk the public relations disaster that would ensue after someone found it producing a watermark, and any possible corporate backlash from including such a "feature".

    I really don't think that much about my privacy, I'd like to think I'm pretty good to get along with in that way, but I (personally -- someone will hopefully point out valid reasons, but I guess valid reasons depend on who can read the watermark ...) can't see any justifiable reason for said watermarks except for perhaps malicious purposes.

  • Sorry for being a little offtopic, here. Back in the day of manual typewriters (no electronic parts whatsoever) each typewriter had-- by virtue of the idiosyncrasies in letter alignment, imprint depth in paper, ribbon wear, etc.-- what amounted to a unique fingerprint. Many famous criminals (The ones that leap to mind are Leopold and Loeb [idsonline.com], two precocious 14 year olds who read Nietzsche and then decided to kill an acquaintance so as to prove their status as Ubermenschen. This was back in the 1920s-- probably those violent 1st person video games that drove them to it) were tracked down because of their typewriter. It wasn't the most damning piece of evidence (one of the kids also dropped his glasses at the scene), but was none the less integral to the trial.

    Again, food for thought.


  • by weston ( 16146 ) <(gro.lartnecnnac) (ta) (dsnotsew)> on Wednesday December 08, 1999 @10:26AM (#1474528) Homepage

    From the article:

    While there is currently no U.S. legislative requirement that manufacturers of copier technology include IDs on color copies, it is also the case that these manufacturers have the clear impression that if they do not include such IDs, legislation to require them would be immediately forthcoming.

    Hmmm. OK. So cooperation is used to forestall regulation. What with the proliferation and strange application of various laws, I'm actually more comfortable with manufacturer cooperation than regulation.

    From Michael:

    But embedding serial numbers in all printer output? Maybe I just have a cynical mind, but I can think of about a hundred reasons this is a bad idea.

    The only threat I'm able to think of at the moment is to anonymous free speech. So if someone prints a newsletter with ideas someone doesn't like, the newslettter is branded "subversive", and can be tracked back to the printer. But then what? Can they really be shut down? And how many such "subversisves" really are anonymous anyway?

  • Is this really serial numbers? Or is it just detection of the 'flaws'. My understanding was that all photo copiers have scratches on their glass or elsewhere that make them identifiable. Similar to how guns are scratched and therefore identifiable. Or typewritters. I would imagine that anything that has mechanical parts and outputs physical media would have some identifiable marks. Merely by the scartchs marks etc on any mechanical device.
  • by rde ( 17364 ) on Wednesday December 08, 1999 @10:29AM (#1474534)
    The article says that we may see this sort of thing implemented in ink jets soon; I'm hanging onto mine.
    Ink jets have come a long way in the last few years, and they've reached the stage where, with the right paper, they can print photographic-quality pictures.

    What does this mean? Well, everyone who's planning on doing something nasty-and-traceable will do it on an older printer. Some stupid people won't, and they'll get caught, justifying in the minds of the Man and the public that such watermarking is worthwhile. But, like drug smuggling, the vast majority will slip by unnoticed.

    Freedoms will be curtailed, money will be wasted, and it'll all be for nothing. Have a nice day.
  • by British ( 51765 ) <british1500@gmail.com> on Wednesday December 08, 1999 @10:30AM (#1474537) Homepage Journal
    On a news segment, it showed one brand of copiers that messed up a dollar bill being copied on the printout. THEN they showed you how to circumvent it(gotta love those news people). You also put on a color photo when you're copying the dollar bill, and boom, instant copy defeat.
  • If I use my color printer to print counterfeit money, and the printer embeds some kind of serial number in the printout, how do they know it's *my* printer? I mean, I don't have to register the software or anything. And even if, I probably wouldn't give them the printer's serial number (or my real name, for that matter) if I was planning to use it to counterfeit money.

    On a separate note, watermarking software has proven to be useless, since just loading and saving a jpg gets rid of it (and if that is not enough, just change the brightness slightly, or apply a "weak" filter). I don't know if any method exists yet, that really survives printing out and rescanning (I can't imagine that's possible. It's hard enough to get even close to the original colors with most current scanners and printers).
  • to identify "original" impressions? I'm thinking of the case of digital cameras/camcorders where you need to use the results as evidence in say a court and you wish to verify that any resulting image is the true and faithful record rather than a digital marked up version. The abuse of technology to fake evidence, influence a constitutent or pervert the course of justice, either deliberately or by chance [informinc.co.uk]) can be a danger to a society which increasingly requires a informed evaluation of rather complex issues. Already artists think nothingabout touching up their works. Given the increasingly use of synthetic imagery, how much further will it go before we trust anything we see or hear? Perhaps this will follow the case of rubies where the artificial ones are so perfect, the real collectors items are those with natural flaws which are difficult to fake. But with digital media which is infinitely malleable, how can one tell the difference between reality and augmented? Think of the increasing use of artificial substitutes for money (book tokens, phone cards, gift vouchers, etc) .... how easily can these be faked, especially in digital form? As a fiat money, the dollar bill represents nothing except a promise backed by the trust and faith of the people for a future claim on some resource, good or service. Laws and technology may be fine, but they are no substitute for personal trust and eyeballing the system to make sure there are no hidden gotchas.

  • by meckardt ( 113120 ) on Wednesday December 08, 1999 @10:35AM (#1474546) Homepage
    Privacy concerns aside, the only thing about placing an identification number on a color print that would bother me would be if I could see it. If the ID was scattered about the page as "noise", and unobservable by me, it wouldn't bother me much.

    As for the privacy issue... wouldn't such a encoding method be proprietary to the manufacturer? So what happens if I first copy the color image on a Xerox machine, and then take the copy over to a different machine, and copy that. Assuming the quality was not lost, the hidden ID code would not be decipherable by any (one) decryption algorythm.

    Mike Eckardt [geocities.com] meckardt@spam.yahoo.com
  • All sufficiently complex copiers require manufacturer service, as the manufacturers are loathe to give up the lucrative service contracts. The owner of a particular ID is therefore known to the manufacturer by-way of the machine serial number. Even if the manufacturer can't tell you who currently owns the machine (if it is not being serviced) they can tell you the serial number of the machine that produced the copy.
  • I would believe physical defects rather then some type of "hidden in the noise of the picture" type of watermarking for purposes of identification. What type of process would it use to hide an "invisible" watermark into a printed image. Also, how would the watermark on the printed page be effected by age, weather, water, dust, and sunlight?

    I would even believe that the copier companies might be putting scratches on the glass purposely for that. But the idea of a secret hidden function is just too over-the-top. The damn machines are complex enough without sometype of super-chip that adds an invisible watermark. Also, what about analog color copiers?

    Just my two cents.
  • by Anonymous Coward
    The United States constitution does not specically grant a right to privacy. However, the supreme court has on many occasions upheld this as a basic American right. Many states constitutions specifically include such a right. California is one example.

    Technology that identifies copies and printer output infringes this right. If every print out and every copy identifies the machine from which it came, private communications from these media are impossible.

    Your employer will have to begin a policy where documents that are not lawyer approved will have to be shredded, lest something you printed in jest make it into the 'wrong hands' and the person or company sueing for libel gets a court order to identify the documents origin.

    Aside from possible government abuse of this technology it is also possible that the 'propriety algorithms' used to ID machines could be broken or stolen. Given the history of these types of secrets, I would say it is inevitable.

    The worst harm I see here is more fuel for the fire of tort cases. With everyone sueing everyone else I can see this technology adding fuel to the fire.

    I can not think of any specific scenarios where the average law abiding citizen would be harmed by this unless the government were to abuse thier power to identify documents. However the less power the Government has to infringe, the less they will be tempted.

    -AC cause I can't remember my /. nick. =(
  • many of the large chains give you a big hassle about copying regular itmes, much less money. The debit cards they so frequently use for convenience (and they are more convenient than change) can also be used for identification.

    As an artist, I've had copy places refuse to let me make photocopies of my own work because they were worried about copyright violations (I just couldn't convince them that i had in fact created the work in the first place!)...
  • ISTR reading that in the old Soviet Union, anyone who bought a typewriter was required to register a sample of their type with the state. (For you young pups out there, old mechanical typewriters used to have enough variations in the print heads that you could supposedly identify a typewriter from a print sample. I doubt that survived the invention of replacable daisy wheels, IBM "ball" print heads, etc. Modern manufacturing techniques may well have started producing identical print heads well before that.) The CCCP supposdly wanted to be able to identify the source of any subversive propaganda. I suspect this may have been an urband legend; it has a sort of "too good to be true" feel.
  • It wouldn't be that difficult really. If they can track the watermark back to a particular manufacturer then the manufacturer will have the SN and the outlet that it was sold to on file. They then go to the retailer and try and find out who the SN belongs to.

    The only potential way around it I could foresee is to buy the equipment from a computer show and pay cash for it.

  • My understanding is that it's microscopic - the arrangement of the dots on the paper. To the naked eye, the copy is perfect, but under a microscope things are very different (same with plain B&W photocopiers.. ever looked at copies vs. originals under a microscope?)

  • What good is a serial number that's not registered? None at all. It doesn't make sense in any context EXCEPT that we will be forced in the future to register our serial numbers. Creeping incrementalism at its finest.
  • There are techniques for hiding information into pictures. For example, some pgp 2.6.1 rpm's distribution comes with some stuff for this. If this was done, I don't know how you could remove it. Perhaps changing the image format a few times would remove it (and picture quality) from the conversions.
  • by Cuthalion ( 65550 ) on Wednesday December 08, 1999 @10:50AM (#1474576) Homepage
    This is technology that Adobe licensed from [adobe.com]Digimarc [digimarc.com].. One of Digimarc's services they offer is you pay them some money and they report any use of your image they found on the web. By keeping an eye on my logs, I've noticed their crawlers perusing my server several times. Though all of the images on my site are mine (MINE MINE MINE!), I still don't like this idea.

    I wonder what sorts of transformations these technologys are impervious to.. Since they're looking for on the web for watermarked graphics, presumably colour reduction (gif) and/or jpeg compression artifacts don't disrupt things. Will a slight blur or rotation? Can you embed an extractable watermark on white noise?
  • by davie ( 191 ) on Wednesday December 08, 1999 @10:50AM (#1474577) Journal

    The SN may not lead investigators to your printer, but if you're already a suspect and the good, er bad guys (it's so hard to remember which one the cops are these days) have your printer, they can prove that some insidious document was printed on your unit, then all they have to do is try to convince the nice folks on the jury that you were there when the document was printed.

    Should we worry that someone has already come up with a universal printer make/model ID that appears on all color copies and that this little detail has remained a secret? How likely is it that ABC Copier Company would say "No" to a court order demanding the name, address, phone number of the customer on the warranty registration for a particular printer?

  • What is the most effective way to fight this? I suppose we need to let the printer companies know that we have no intrest in purchasing watermarking printers.

    Also, the whenever a printer company releases a new printer someone needs to find out if they have included watermarking.. and post it to slashdot if they have.. one would hope that we could make enough commotion regarding the printer to cost the company money.

    Do any printers corrently on the market support these features? It seems to me we need to send a message to the companies that going allong with the Gov. will cost them money.

    It is also a good idea to get out information on how to preform the hardware modifications to change the serial number as quickly as possible. It seems to me giving the script-kiddies the ability to get someone falsly convicted of counter fitting just by examining a page the someone printed out will go a long way towards killing these things.. and will force people to only purchase printers which do not use watermarks.

    Any more suggestions?


    BTW> Actually, the false convictions thing is an excellent way to fight many of the `ID the public' government programs.
  • But, given the wide variety of designs used in US postage, how would a copier recognize a stamp?

    If it did, wouldn't people get hosed by innocently copying an envelope for the address information?

  • At one point [Romanian dictator Nicolae Ceausescu's] censors intercepted some anonymous letters addressed to Radio Free Europe, criticizing the Ceausescus' 'personality cult.' In a fit of rage, Ceausescu ordered
    his security chiefs to get samples of the handwriting of every school child and adult Romanian, so that their handwriting experts could identify who had written the letters.

    Additionally, he wanted every typewriter owned by the state registered with the Securitate, along with a sample of its type.

    --Dr. James McCollum (Is Communism Dead Forever?)

    What is interesting is that this is the same dictator who was finally ousted by the people after he failed to suppress a coup attempt against him and the media caught wind of it.
  • This all sounds kind of suspect to me. AFAIK, there is a certain amount of noise involved in any existing method of digitally scanning an analog image. (In fact, SGI's LavaRand [sgi.com] random-number system is based on this principle.) I find it hard to believe that any "watermark" as well hidden within the image as the article suggests wouldn't be lost in the process of scanning it back into digital form.
  • by cyanoacrylate ( 47864 ) on Wednesday December 08, 1999 @10:55AM (#1474588)
    I saw some earlier concerns about the tracability of a particular printer... The watermark contains the serial number of the printer. Previous techniques of forensic science already allow us to identify printer makes and models, so the change in watermarking will not assist law enforcment at all (aside from possibly knowing which store the device was sold at), as long as you just don't fill out that product registration card...

    Which no counterfeiter would do anyways.

    So why bother at all? It will make printers more expensive, and the government thinks that they get a tool to assist them in enforcing the law, but doesn't really - other coroberative evidence will have to be collected to get near enough to the printer with the watermark to check, and then traditional forensic science techniques could be used.

  • I really don't understand the point of getting excited about this. The police can probably already match paper and ink, and minute impressions in the paper from handling to identify a specific printer.

    All this would do is make the job slightly easier.

    Dead tree copies aren't the big thing copyright holders would be afraid of, either. They are lossy copies.

    The only major reason I could see this being worth anything would be to catch people printing kiddie porn or money.

  • ...for some reason, like a record of who it was sent too. Then your fscked up.
  • by Anonymous Coward
    There will be a thousand ways to circumvent such technology. The image, remember, has to eventually make it to paper.

    So, then, let's assume that the watermark is inserted into the document at the hardware level; i.e., you can't send the printer any specific data to disable said watermark.

    The first issue is old printers. I have an HP DeskJet 812C on my machine. Very nice resolution-- in fact, I could probably do counterfeit with it quite easily (if I had the patience to watch my printer run for hours on end). Strike one against the gov't-- it's too late to stop the old printers; criminals can just buy 'em second-hand.

    The second issue is how fine a resolution the watermark will use. Will we wind up with watermarks on documents at 150 dpi? It'd be pretty pointless-- a counterfeit bill printed at that resolution would be pretty easily detected. But what if I can get a *very* precisely aligned printer that runs at 150 dpi, and print the same image (or layers of the same image, as it were) on the exact same location? It'd take some doing, but it could be done. If this proposal is to stop a "casual" counterfeit, then it may be useful, but I really doubt it-- it's going to be too easy to find out how to beat the watermarks.

    Now, though, let's get to the real meat of the issue-- what if I have bad print heads? No, seriously! If I let the heads on my printer get clogged or whatever, it can result in a noticable reduction in print quality. So, if I can do it just right, I can print out my counterfeit bill at twice the needed resolution (i.e., the resolution needed to make it look real). Because the ink is running and bleeding and such, any watermark would most likely be destroyed. But the dollar bill might not look all that bad-- especially after I run it through the washing machine in my pants pocket once or twice (which many counterfeiters do, partially to make the dinginess seem more like regular wear and tear, and partially to give the bill a better texture).

    I really doubt this proposal will go far. Even if it does, there will be ways around it. Don't worry yourself too much-- I know I won't...
  • Well, when I last bought an HP 612C (a printer that's a few years old model), the store recorded the serial number off the box on the receipt (and in their computer system).
  • Check the newer designs. They've been in use for several years now, but because of the way the Treasury decided to do it they haven't made their way into the smaller bills yet. So far $20 bills and higher have been converted; $10 is due in 2000 (with $5 in 2001, and finally $1 in 2002). Security threads, watermarks, moire-inducing patterns, and my personal favorite, the color-shifting ink. This, along with the red and blue fibers, hidden pictures (like the spider on the current $1 bill), the paper itself (yes, the paper itself is considered a security feature; many counterfieters have been caught when cashiers realized that the paper didn't feel right), and the other stuff from the current bills.

    I don't like the look of the new bills as much (except for the aforementioned color-shifting ink, which is simply too damn cool for words). But they should work a lot better for this sort of thing.

    Yeah, the US bills were certainly due for an update (no changes at all since the mid-70's, and no major changes since the 1920's). But they're getting it, finally. I think it would have been cooler to print the whole bill with the color-shifting ink, though.
  • I agree that this is ridiculous. But as far as the any company who did do it, how would the average person know? I had no idea that some companies already did something like this until I read this. As for a reason to vigorously fight this type of thing, let me pose a hypothetical situation. For example say person X had serious moral objections to Scientology (just for the sake of argument, no disparagement implied) and waged an anonymous campaign against what he perceived to be wrong. Some people could agree with him others maybe not. But the Scientologist's having a lot of money and power use the watermark etc on his copied fliers to track him down and either sue him or whatever. Is the fact that they located person X and possibly shut him down a breach of free speech? I think that this sort of thing has very serious implications much wider than what it appears to be on the surface.
  • I've seen this first hand. Feds have long been able to detect watermarks from colour laser printers.
  • Pretty simple.. by the serial number.. they ask the manufacturer, who finds the distributor, who finds the user/person who purchased it.

    (OK, maybe not _THAT_ simple :o)

    They generally rely on the fact because color copiers cost thousands of dollars, that nobody ever pays cash for one, so there is a paper trail to follow...

    It's not flawless (yes, you could pay in cash, and wear a disguise and surgical gloves, and drive away in a stolen van with false plates..) but it's enough to give them a starting place to look for their suspect.

  • Not quite as simple as that... (Sorry for all you patenters :-) ). The signature is embedded in the image itself, through 'random' noise. Definately fun stuff, untill some big co's heard of it.
  • If the "duplication device" is deliberately modifying the output without any control by the operator - then the machine is not a "copier", and the producers should be liable under whatever "accurate advertising" legislation is prevalent in their markets.

    Yeah, like that would actually happen...

  • by Millennium ( 2451 ) on Wednesday December 08, 1999 @11:05AM (#1474620)
    This is a gross privacy violation. However, it's not too difficult to circumvent.

    Consider: the serial numbers can only be traced back to the printer, not the printer's owner (at least, not without records). Also, consider that the serial number has to be stored someplace where it can be modified easily, so that the printers can still be mass-produced. This means that it's still theoretically possible to modify the serial number.

    Hehehe... my guess is that they'll use letters in serial numbers too, to allow for a greater number of numbers. This means that, once we figure out how to hack these, it'll be possible to put little messages into the watermarks.

    I can see it now... Big Brother tries to read the watermark, all they get is strings of swear words :)
  • by Greyfox ( 87712 ) on Wednesday December 08, 1999 @11:06AM (#1474623) Homepage Journal
    Sounds like a great way to make the lives of the people at Kinkos a living hell. Find a print sample that sets off the board and incorporate it into your letter head... Then just lurk in at odd times and leave a trail of black-copying color copiers in your wake...
  • If it did, wouldn't people get hosed by innocently copying an envelope for the address information?

    What if I just want copies of my private stamp collection so that I can show people what I have without risking it? If you invest several thousand dollars in stamps you don't want them stolen.
  • by debrain ( 29228 ) on Wednesday December 08, 1999 @11:08AM (#1474625) Journal
    Well, I've seen several solutions to the counterfeit problem. They are as follows:
    • Holographic images to which there is no consumer equipment to duplicate
    • Coins. I hate them, but the printer likes them about as much as the VCR does.
    • Digital money. A whole other arena of counterfeiting arises with digital money (Visa, Interac, etc.), but they obviate the necessity of preventing hard-copy counterfeiting.
    • Fingerprint/unique identification procedures with point-to-point transactions from a secure database. This has serious implications, which I won't go into, but it does obviate the whole counterfeiting thing (within reason -- fingerprints are pretty easy to replicate, but Iris/Genetic scanning is better.)

    Not that we'd ever use $50 coins (it'd suck to lose one, presumably, depending on inflation), and holographic equipment can probably be rented or stolen or bought for a *reasonable* price but I do not know if counterfeiting money would justify a hefty-costing hologram printer (I have *no* idea how much they cost), and electronic money has it's own problems. (such as a controlled economy by an invisible hand.)

    Some day, we may have to resort to using genetic code to identify ourselves, and our purchasing power will probably depend on what some database tells us. :) I jest, but it's not too far a cry off from reality.

  • Canada recently (well, 10 years ago) changed it's paper money so that bills over $10 have a foil "hologram" on them..

    And about 5 years before that, they changed it from looking like American money, to looking like Monopoly money...

    It was interesting that when the new money was introduced, there were a few reports of couterfeiting, by (and I'm being serious here) photocopying the bills onto consruction paper and coloring it in with a wax crayon. (They showed some of the bills on the evening news - they were so bad that a child should have known - the coloring didn't even stay inside the lines!).. I guess it's amazing what a convenience store worker will believe..
  • Are there any effort going on at reverse-engineering/removing this 'feature'? I assume that since it's been known for years, and simply not publicized, that somebody has been working on this.

    Well, if you notice your printer or scanner is doing some funny identification stuff on your work, let me know.

    Imagine a scanner as an optical sensor that scans a page. The sensor will output this raw information to a processor, bit by bit for the image. If you have a patterned image, the stream will reflect that image. You can make your own test equipment from a number of programmable microprocessors out there and recreate this image. From there, compare it to what the scanner puts out.

    Same with printers, except there is lots of math involved to optimize the the non-linear ink jets and static attractions on laser jets. It all depends on how much time you want to spend tracing the process.
  • by jd ( 1658 ) <imipak.yahoo@com> on Wednesday December 08, 1999 @11:10AM (#1474631) Homepage Journal
    This should be relatively easy. Watermarks are, by definition, digital images. If you have something in your print driver which automatically adds that same digital image, in inverse field, then you would essentially filter the entire watermark out.

    A second alternative is based on the premise that such an image is necessarily going to be faint, to prevent it obscuring what you're printing. If this is to scale with your print-out, then simply print your image much fainter (making the watermark effectively invisible), before reprinting the image upside-down on the same page, with the paper also inverted. This'll put a second copy on the paper, making it normal-strength, but the watermarks will only overlap in places (one being 180' to the other), so rendering most of it invisible.

    Finally, switch back to a daisy-wheel. I don't care =HOW= good a manufacturer is, they can't make a daisy-wheel print watermarks, come hell or high water. Besides, daisy-wheels are great for listing print-outs. That is, if you want to turn the recipient into a gibbering idiot. :)

  • What if? What if I print a page and it is uniquely watermarked? If I am not in breach of any laws, where is the problem?

    There is always a knee-jerk reaction to things like this, but think about it. All this allows is for somebody, (presumably) in authority, to find out what machine printed/photocopied a page which they already have in their possesion. It is not sending copies to bigbrother@everygovernment.com.

    What kind of intrusions may be present here?
    Let's see...

    • They can tell that a love-letter sent to your mistress originated from you. Are you listening Mr. Starr?
    • They know that the nude pictures of P. Anderson are yours. The fact the were under your mattress didn't tip them off...
    • They have proof that you printed off 500 flyers for your local nightclub. Shame on you.

    More importantly, they can track counterfeiters, blackmailers, child-pornographers, stalkers, and abusers of copyright, among other things.

    Remember: Before any tracing can begin, the page be in the tracers possesion. And at this point, they have already served a warrant, or invaded your privacy. Next thing they'll start uniquely identifying the car I drive...

    More interestingly, how difficult is it to forge these anyway? Can I register a personal 'Pretty Good Paper' signature based on the
    watermark my printer produces?

    Do they include timestamps? If so, I'm buying the best there is next time I want to copyright something...

    "A goldfish was his muse, eternally amused"

  • by Anonymous Coward on Wednesday December 08, 1999 @11:11AM (#1474634)
    I once worked in a small corporation called MicroAge, in which no one really payed attention to anything concerning computers (except Help Desk Support) as they were too busy making impotent, er, I mean important management decisions.

    So one of my co-workers attempted to copy a dollar bill off the photocopier. It really did start printing out all black sheets of paper so he clocked and went home. (He had used a supervisors ID to use the machine).

    Bemused I watched as the next day (showing off to his friends) he brought in some bleached single dollar bills and managed to scan in a twenty dollar bill. He conned our graphics guru into performing the necessary touch-ups (removing the seethrough portions for instance) and divided the image into the front and back.

    Next he removed the little metal strips from 10 5'ers (he later just passed them out for change and no one noticed the missing strips). Somehow he managed to drag the strips through the 10 bleached dollar bills in the appropo spots.

    After printing off 10 of them he promptly went to the bank to attempt to get larger bills. Which he successfully did.

    Unfortunately for his stupid ass the bank later performed full tests on them, and reported the counterfeits to the FBI and National treasury. (The latter who confiscated the bills to go into counterfeit research). The FBI actually managed to lift an ID from the bills, and tracked the machine to the office.

    I noticed we had a new employee outside our normal hiring schedule one day, and promptly had my friends evacuate the area and dissavow all knowledge. To make a long story short, he's in the pen, and I have a new cubicle =).

  • by jedrek ( 79264 ) on Wednesday December 08, 1999 @11:15AM (#1474637) Homepage
    If anyone has ever encountered a digital watermark of the Digimarc kind, (Photoshop users know what I'm talking about) there's an easy way to remove it. Resize your image to 95% of the size then resize back to 100% - minimal loss of quality (especially at high resolutions) and no watermark.

    This is just an example but Digimarc underlines two serious problems with watermarks:

    a) No watermark is invisible. No matter what anyone tells you adding watermark is a lossy process. The harder the watermark is to remove the more visible it is.

    b) Watermarks will always be removable. If you have physical access to the machine creating the watermark (scanner, printer, whatever) you'll be able to edit/disable the watermark. Unless you embed the watermark in the paper fiber or something (but then you're tracking the media, not the data) it'll probably be enough to cut off part of the image or something similar to disable the watermark.

  • by Anonymous Coward
    well, if you want to look at wierd money, check out australian money. the aussie gov. hated counterfeiters so much that now we all have plastic money, no, not credit cards, I mean *plastic* money, chock full of holographs, hidden pictures, everything. and if you fold the 5 dollar note in a special way it looks like the queen is giving someone a blowjob. heh.
  • They are releasing new $5's and one other in about 5 months, and they already did the $20 and $100 .... they have watermark,magnetic strip, color changing ink, microprint, its made out of some fabric, and has lots of crap you cant create with a photocopier...of course since the older bills can be used people can copy them ... when other countries change their money do they totally wipe out the use of the previous?

    $mrp=~s/mrp/elite god/g;
  • by Anonymous Coward on Wednesday December 08, 1999 @11:32AM (#1474653)

    Canon color lasers (800, 1000, 2400, ect.) all have a board that recognizes things like money and postage stamps. If you try and copy any of these it will spit out all black copies, and will continue to do so until a Canon tech is called. (They usualy call the Secret Service)

    Shifting to AC mode for obvious reasons,

    Older Canon copiers (CLC 1, 100, 200, 300, 500, 550, and 700/800) all will recoginze older US currency (and presumably other currency overseas) and produce a black/green mask over the copy. They will not, afak recognize stamps.
    Occasionally, they throw the mask on a specific green, combined with scroll patterns that trips the DSP's currency detector.
    Contrary to popular myth, these errors do not lock the copiers up, but they do produce an error, that is logged in the same place that jams and such are. Most companies require their technicians to report these errors and to cover behinds, such errors are reported to the Secret Service.

    The older copiers, though, have a hard time recognizing the newer currency designs and will copy them quite well (or so I understand)

    Newer machines (CLC 900/950, 1000/2400, 1120/1150) though, will not throw a currency error at all! These are the ones with the "hidden" barcode that identifies each copier.

    BTW, if you want to see the code, look closely at the white areas of a copy, you'll see fine, yellow dots. This is the encoded patern.

  • olographic images to which there is no consumer equipment to duplicate

    Could holograms lead to a false sense of security? Would money imprinted with holograms be ultimately secure?

    With some basic equipment that can be purchased from any number of scientific supply catalogs, I could create my own holographic images in a homebrew photo lab. Now, they won't be identical by any means. A good side by side comparison would reveal that they are indeed very different. However, to the average person who notices a fancy schmancy hologram won't have the memory of the detailed original hologram.
  • by Signail11 ( 123143 ) on Wednesday December 08, 1999 @11:35AM (#1474659)
    Ross Anderson and a team of other researchers wrote a white paper entitled "On The Limits of Steganography" published in the IEEE Journal on Selected Areas in Communications Special Issue on Copyright & Privacy Protection, vol. 16 no. 4, pp 474-481, May 1998 (it's available online at http://www.cl.cam.ac.uk/~rja14/ ) that deals with the issue of robustness of watermarks and other forms of information hiding. The overall conclusions are that:
    -Robustness decreases proportionally with the square of the information contained
    -Watermarks can almost always be either distorted beyond recognition (if the information content is high) or removed (if the information content is lwo) using a simple sequence of transformations, ranging from smearing spectral power peaks to scaling the image
    -It's almost always possible to determine that watermarks or steganography was used because the entropy of the bits affected is most probably higher than that of the surrounding message.

    Flames? Think I'm a karma whore?
  • by kill bikini-bot kill ( 117481 ) on Wednesday December 08, 1999 @11:36AM (#1474663)

    ... and this is something we've known about for years. Most color copiers do embed a serial number and many--particularly canons--will shutdown if you try to copy currency.

    While the owner of the copier may not be officially required to register with the manufacturer, most non-consumer grade equipment needs to be serviced at least once a month. For example, each color copy generates a small amount of excess toner which is scraped off into a waste toner bottle; Xerox decided not to make this a user serviceable part on the Docucolor 40's (which are in almost every Kinko's in the world).

    Kinko's, however, is generally more interested in making money and avoiding lawsuits than invading anyone's privacy. Every Kinko's Co-Worker is trained in the copy guidelines generated by our pack or ravenous lawyers about what we can copy and how. For example, the kid in the article should of been told that we can copy his driver's license but only in black and white and only at 129 percent.

    Anyhow, for your extra dose of paranoia today consider this: even most of the new black and white copiers (from the Docutech to the Xerox 265) actually digitize and and store the images rather than flashing them to an analog transfer belt. All these copiers are equiped with a modem.

  • I'm not liking the sounds of this plan. And initially I was thinking that hey, as long as I have my current printer that does fine, no worries. However, all it would seem to take is a driver upgrade, and zap, your currently private printer is now id'ing you.

  • If you want to determine what the watermark is, just:
    1) Scan your image.
    2) Scan it again, only shift it down y inches, and over x inches.
    3) Compare the two scans, allowing for x and y and the DPI of your scanner. The difference will include the watermark.
    4) If the images compare identical, use different values of x and y, or try rotating the image.
    5) Repeat the process with a number of varied images.
  • by G27 Radio ( 78394 ) on Wednesday December 08, 1999 @11:41AM (#1474668)
    I really don't understand the point of getting excited about this. The police can probably already match paper and ink, and minute impressions in the paper from handling to identify a specific printer.

    The things you mention can be used to make a positive identification of the printer...but they have to find it first. The serial numbers, however, can be looked up in a manufacturers database. For those that didn't read the article (I almost didn't but I'm glad I did) here's something interesting from it:

    To read these IDs, the document in question is scanned and the "noise"
    decoded via a secret and proprietary algorithm. In the case of
    Xerox-manufactured equipment, only Xerox has the means to do this, and they
    require a court order to do so (except for some specific government
    agencies, for whom they no longer require court authorizations). I'm told
    that the number of requests Xerox receives for this service is on the order
    of a couple a week from within the U.S.

    In other words, according to the author, Xerox routinely, sometimes WITHOUT REQUIRING A WARRANT, gives out information regarding ownership of copiers based on these ID numbers.

  • The letters on the daisywheel printer or typewriter have their own uniquely identifiable characteristics (fingerprint), as Ted Kazinski has found out.
  • by dattaway ( 3088 ) on Wednesday December 08, 1999 @11:46AM (#1474672) Homepage Journal
    There's always a hardware solution for compromising software.

    Just use mirrors, lenses, and perhaps filters to change the aspect ratio. Do you really think typical DSP software is engineered to a high degree to prevent crafty circumvention?

    Say, on a scanner, have it scan an image that is shown to the sensor as twice its size with a color filter for multiple passes. Then have a software script clean it up. The final scanned image will look better this way anyway...

    Now, if you wish to print that stamp collection out on your compromised printer, you have a few options through hardware. A simple way to fool the software, like the green of money, is to shift the colors, say green to red, red to blue, and blue to green, and do this to the print head connections after your software conversion of the image. If its pattern based, say those grovy lines on certificates that is being detected, why not invert *everything* and put inverters on the printhead? Now, for that, you will need to filter your image so the dots shoot out at the right contrast.

    Hey there's a black van outside, let me check to see who it is...

  • Disclosure: I work for Xerox but in a manner unrelated to copier/printer design. I have no inside knowledge of what is done or how they are done

    A quick search of IBM's patent database has uncovered the following:

    Anti-counterfeit pattern detector and method [ibm.com]

    Digital watermarking using conjugate halftone screens [ibm.com]

    Methods and means for embedding machine readable digital data in halftone images [ibm.com]

  • by lcddave ( 52945 ) on Wednesday December 08, 1999 @11:59AM (#1474690)
    For most consumer level inkjets, it seems most imagine processing (print description language processing, rasterization, etc.) is actually done on the host computer with the printer just basically being told put a dot here with this much color.

    Thus, it could be possible for this tracing technology to be retrofitted to an existing printer via a driver upgrade. (Oh you're having print problems? May we suggest the new driver...)

    If the serial number were still tied to the printer it would require some bi-directional communication. But that already exists in most printers host based UI functions.

    But then if you think about it, this type of computer based processing opens up all sorts of other serial number sources. How about Pentium III serial numbers, ethernet MAC addresses, etc? (And haven't we seen these things already happen before, but only with digital documents?)

    Thankfully, if somebody would probably do a software hack if this really happened.

    How's that for paranoia? =)
  • Just time in milliseconds the ammount of time it takes on something you know that dosn't have the watermark to something that does...

    Yes, and this can be measured down mighty close to individual clock cycles directly from the image passes. If a greater precision of software analysis is needed and the extra hardware at hand, just feed the sensor data from a previous pass. From there, a single branch of excecution would yield a detectable delay of output on the changed image.

    Paper. Someone needs to tell the spooks and manufacturers to leave my scanners and printers alone so my artwork will not be compromised.

    Whatever happened to gold and silver currency anyway? Nothing beats the fascination with gold. Paper just don't cut it. It can be copied, cut, shit on, etc. Gold can always be given as a gift, reworked, melted, but it will always retain its lust. There are many metals that can be compared to gold. I work at a copper power cable and wire manufacturing plant and if I stare at the product long enough, I feel like I have walked through Fort Knox. If 1,000,000 pounds of copper could be made into gold...
  • by Anonymous Coward
    ...who had any type of importance...

    So, it's ok if government representatives kill those unimportant people.

    Unimportant people:

    • Vicky and Sammy Weaver, former residents of Ruby Ridge [constitution.org]
    • David Koresh and many of his followers in Waco [anglianet.co.uk]
    • Allison Krause, Jeffrey Miller, Sandra Scheuer, and William Schroeder, all students at Kent State [floratec.com] in 1970.
    • Ezequiel Hernandez, killed [chron.com] while tending his goats on the Texas Border.

    I'm sure there are many more, but I think the point is made.

    I hope you're certain that you are important to the government.

  • How's that for yet another reason to go Open Source?

  • Yes, you can still print your own money. For now.


    Be sure to buy your scanners and printers with cash.

    However, your family pictures will bear the mark of mathmatical noise. This is what its all about. Do you want your baby's picture to be tainted?
  • If the Secret Service thinks you've counterfeited something, they can try and obtain a warrant to get your printer's serial number. If it matches the watermark, they have another piece of evidence.
  • How about anyone executed on death row. Surely it is a federal employee who puts them to death,or a state employee at the very least, which in my opinion can be viewed as the same for this argument. Regardless of what level you look at it from, whether it is the person throwing the switch (or however else they do it), or the justice who permits the death penalty, someone representing government kills this person.

    Unless, of course you want to get in to the argument of the person killing themself by putting themself in the position in the first place. (Which I don't)

    As for the importance issue, obviously these people are important to someone. Additionally, anyone in this situation is important to the system of laws in this country by establishing further precedent for the death penalty.

  • This is quite simply not true. Modern Digital Watermarking is not visible to the human eye, but encoded in the low order bits of the color infomration of an image. They can be engineered to present a tradeoff between visibility, resistance to removal and number of bits for the embedded ID.

    There are certainly some schemes that can withstand the image being cropped, resized, and even sometimes printed and rescanned. If you've used a copy of photoshop in the last couple of years, you should have seen it check every image you scan for an embedded watermark.

    There are similar schemes for audio, and they don't necessarily require digital media. Again, there is a tradeoff between resistance to transformations, number of bits in the watermark and audibility.
  • by WNight ( 23683 ) on Wednesday December 08, 1999 @12:23PM (#1474716) Homepage
    Great, we imbue a token with some value, then when easy creation of that token becomes possible, we outlaw such creation instead of picking a new token?

    So, pacific islanders should start massive projects to poison sea creatures with shells, to prevent the devaluation of a shell-based economy? And those people who use large carved stones for money, they should outlaw a hammer and chisel?

    You know, it'd be easier to simply change the tokens we use. If paper is hard to copy, then use coins with a chip in them, or somehow printing into the paper of the bill. If that proves impractical, either use tokens of a real worth (ie, gold) or use digital tokens and drop the whole idea of physical cash.

    But, don't outlaw basic tools, or cripple them, preventing us from creating many things, just because we might forge a token.

    The only way to preserve the value of cash is to make the cash inherently valuable, or to pick a token that can't be copied. If the colors and design of the bills can change, why can't the basic type of money change?
  • The answer to that question depends on the algorithms in question, but in all likelihood, the second watermark would be detectable, and the first watermark might still show up. These things don't work the way you'd necessarily expect... as have been evidenced by hordes of posters on this topic.
  • >>Well, actually, they did kill Patrick Henry. Actually, they didn't. He went on to become governor of Virginia, and proceeded to do his very best to dispose of the the liberty of the inhabitants of that state. (and was cordially hated for it by Madison, Jefferson, et al)
  • Here's a link [microtaggant.com] to a company that deals exactly with this kind of technology.
  • Why go to all this damn trouble? I've never understood US currency, and I live here.

    Look at Australia's currency. The bills are mostly plastics. Nearly impossible to crease them through normal usage, tearing is extremely difficult, each one is multi-colored, and each and every single one has a CLEAR plastic window with printing on it that is part of the bill. You aint copying that with standard consumer equipment no matter what the hell you do.

  • Does anyone know if CDR drives contain logic to apply "watermarks" to burned discs (thus associating the disc with a particular drive)? Does anyone know if there are any plans to introduce such a "feature"? (And what kind of programmer would agree to write such software?)


  • Try http://researchweb.watson.ibm.com/topics/popups/in novate/multimedia/html/dahow.html [ibm.com] for one introduction. A more thorough background piece is available at http://www.dlib.org/dlib/d ecember97/ibm/12lotspiech.html [dlib.org] or http://www.jtap.ac.uk/reports/htm/j tap-034.html [jtap.ac.uk]

    I hope this helps anyone who likes reading research.


  • Very funny stuff here. The CLC-1, 200 and 500 were unable to detect cashola on the copy glass. With the intrduction of the 300 and up (550, 700 and upto the 1000) the anti-counterfieting logic was built in. It is not able to actually recognize the image of money. It recognizes the color of green. So yes certain images will not reproduce. One of my old customers would copy about 15k worth of golf course pics from around the country. There were about 1% that would print with the green mask over the image. That is if the lamp was new and the scanner had a recent ccd adjust. As it aged the error would become more frequent. None of the machines ever recorded the error or the scan in any way. Even if they did you could always just clear the ram on the DC controller! The counters on all these machines are mechanical. The serial number on all these machines has been recorded on each copy since the introduction of the 550. It is done in yellow and is not in the image. ;-> With a lupe you can even see it.
  • by Anonymous Coward on Wednesday December 08, 1999 @12:44PM (#1474739)
    First, we need to acknowledge that from the point of view of the US Government, there is a problem [house.gov]. Currently, 40% of succesfully passed counterfeit currency in this country was created by an inkjet print mechanism. With the increasing availability of digital image processing equipment to consumers, the integrity of our currency will be increasingly at risk unless something is done.

    Second, consider this problem from the point of view of the imaging equipment manufacturers. They clearly do not want to have some ill-conceived legislation rammed down their throats, that mandates some expensive technology be put into every device built. Even worse would be if every nation they sold too had different regulation that needed to be complied with.

    So, the manufacturers with foresight are cooperating with the government to try to come up with inexpensive solutions that make the government happy.

    Now, keep in mind that anticounterfeiting is distinct from encoding distinct marks into documents. I'm going to talk about the former first, and will come back to the latter.

    As the original article pointed out, there are already both anti-counterfeiting and source indentification features built into current color copiers. However, these solutions are not necessarily extendable to consumer imaging, because they take place in a closed architecture as opposed to an open one.

    Consider the path that a counterfeit note would take in a consumer based imaging system. It would travel from a scanner, to some image processing software, to the printer. At any point along the way it could be stored, manipulated, or transmitted via the internet. Each step may or may not be carried out by the same individuals. Becasue of this, the most logical place to put counterfeit prevention is in the printing step. The reason for this is that if the protection in the scanning or processing step is broken by any individual, then a print-ready file could be distributed to many others. However, putting the prevention within the printer makes it both less accessable to crackers, and requires that each potential counterfeiter break the protection again.

    Let us focus then on the problem of the printing of counterfeit currency. Three ways of helping to solve this problem quickly present themselves.

    1: Add currency-detecting logic to printers.
    2: Add features to currency that printers cannot reproduce.
    3: Add printer-specific watermarking to printers.

    The trend in ink-jet printers is to make them cheaper and cheaper. Given this trend, it is not feasible to add much computational power to the printer without increasing their cost. For this reason, attempting to do general-purpose detection within the printer is not feasible at this time. This does not preclude, however, doing some quick and dirty detection that is computationally very simple. (For example, is the document being printed approximately 6" by 2.5").

    The design of US currency is unsophisticated, especially when compared to that of other nations. Personally, I appreciate the simplicity and history of our design, but from an anti-counterfeiting point of view it is a nightmare. The latest iteration of our currency was a stopgap effort to try to make it somewhat more difficult to be digitally copied, but most of the new features (except perhaps for the watermark) are not well understood by the public at large.

    Some simple features that could be implemented, easily recognized by the public, and impossible to duplicate on a consumer printer could include:

    1: Printing on a transparant substrate.
    2: (1) with areas that require perfect front-to-back registration.
    3: Printing with reflective (foil)inks.

    But as long as we are creating a new currency, we could consider hybrid solutions. That is, embedding some special patterns in the currency that are trivial for a scanner/printer to recognize, yet do not occur in other document types. This could be some specific geometric pattern, or a specific use of colors.

    So, finally, we come to embedding a watermark in all images printed by an consumer printer. First, be aware that some office printers already do this, mostly color laser printers. But beyond that fact, this is really a separate issue from anticounterfeiting. Printer manufacturers are not going to volunteer to do this unless they are compelled to do so by governments.

    But if a manufacturer were forced to implement this, the most obvious place to do so would be in the driver. This is because (as mentioned earlier) the ink-jet printer itself has little computational resources. The driver has the full resources of the system CPU and is traditionally where the dithering takes place. As far as making the patterns unique, one could either query the printer for a serial number, or simply use the Pentium III serial number, or perhaps the MAC address from the LAN card.

    One closing lesson here, if you were feeling cocky by saying "no problem, I'll hang onto my old printer", then make sure you never upgrade the driver, as that is where this would most likely be implemented.

    Well, in closing, I would love to sign this with my account name. I can't however, so just call me...

    Anonymous Coward

  • Xerox routinely, sometimes WITHOUT REQUIRING A WARRANT, gives out information regarding ownership of copiers based on these ID numbers.

    That's fine for a $50,000 commercial color copier, but how is that going to work for the $93 inkjet that I buy using paper money in WalMart?

    You might catch some numnuts script kiddie with this, but any halfway intelligent person is going to have an untraceable serial number. The problem then is the same as before.. you have to find the printer by other means.

    I think there are much much worse things to worry about than printer codes.

    This [ettm.com], for example.

    Since that article was published, a reporter was able to get tracking information on a local Police Chief. You can imagine the yelling and screaming.

  • > Could holograms lead to a false sense of security? Would money imprinted with holograms be ultimately secure?

    Here in Germany, the most recent edition of larger banknotes already got holograms on them. They are not pasted on the paper but woven into there somehow, so if you just pasted holographic foil on there you would notice it at the first touch.
  • by Ronin441 ( 89631 ) on Wednesday December 08, 1999 @01:08PM (#1474759) Homepage
    The fundamental problem is that US currency is so easy to copy. I have easily enough stuff lying around my office to produce reasonably realistic copies.

    Software aimed at specifically recognising currency and stamps is foolish: it will only recognise certain kinds of currency and stamps; it won't reconise foreign stamps; and it won't recognise other paper instruments which we would rather not see forged (certificates, etc.)

    Software aimed at making forgeries trackable is more thoughtful; but it has obvious privacy implications, and is potentially technically defeatable (as many readers have mentioned).

    The fundamental solution is to make currency harder to forge. Australian currency notes, for example, are printed on a thin papery plastic instead of on paper; they have a piece of artwork partly printed on each side, so it is obvious if the artwork on the two sides is misaligned; and they have a transparent section, so it is obvious if it is printed on the wrong "paper". In a similar vein, the new US $20 note has a "color change" section that looks different when viewed from different angles.

    Trying to fix the problem by limiting the technology in a thousand different scanners, printers and copiers is a bad approach: it's analogous to trying to cover for your lousy encryption by crippling everybody else's computer. The Right Thing is improve the technology in the money itself.
  • by Anonymous Coward

    As a former Kinkos employee, what the Kinkos co-worker said about the legallity of making color copies of official photo id is true. They make you go through several courses in order to teach you stuff about copyright and such. They also don't take chances on stuff, a lot of what can be disputed as "fair use" is not left up to the employee. This is mostly done for Kinkos' finacial safety. This was implimented shortly after Kinkos lost a lot of money from a law suit about how Kinkos made copies of and sold college text books.

    The machines that Kinkos use for color copies are, usually, either Cannon or Xerox. Apparently from the article it is confirmed that the Xerox machines use this serial number id trick, as for Cannon, I have never heard of anything like that from any of the techs that sold and maintained the copiers for us. I do know that Ricoh color copiers only use yellow toner if the item being copied is detected to be money, food stamps, postage, ss cards, passports, etc. I never was able to try it on the Xerox or the Cannon but I'm sure that they have simular features. I was also told, but had it confirmed to be untrue later, that the Ricoh shut down if it thought is was making a copy of one of the later items. The FBI would then have to come in and investigate why it shut down, and once they were done enter a special code to unlock the machine. Like I said this was confirmed to be UNTRUE.

    All of those restricted items that color copiers look for have some sort of clause that allows some sort copy. Money has to be done one sided, B&W and either at 75% of normal size or 25% larger. Most of the others only have to be one sided and B&W. For the gentleman's photo id in the article, a B&W copier would have done fine, I have had to many of them for people using them for things like id for phone companys and such. Never had any problems except from the customer that refused to belive that what he originally asked was illegal.

    The problem with this system of ids on color copies is not a problem for most people. With all the paper flying around the world, no agency or company with an unlimited supply of cash and resources would be able to check the ids on color or b&w copies and keep track of what everyone in a nation, let alone the world, is up to. That right there get rid of the big brother worries that everyone gets when they see the a story about tracking systems. The only people that should have a problem with this system are those who want to and/or do illegal things with digital color and b&w output. Besides the only time Xerox gets requests for id translation would be for something a judge would find worth it, such as counterfiting, fraud, or as a last resort in a difficult investigation. I would like counterfiters to be caught, they only help to raise prices and inflation. Really, there is no other outcome for us do to counterfiters doing their stuff. People who commit fraud only hurt us and some crimminal investigation need all the help they can get and they usually benifit us. I also think that they should get legislation on this soon, that way we can make sure this system is only used for good, like now, and can't evolve to some thing evil. If you are scared, don't be. If you are mad, stop commiting illegal acts. Pretty simple.

    Well thats what I think, it was a long post and it is possibly badly worded/spelled, I apologize for that but I hope you found it informative.

  • Great, we imbue a token with some value, then when easy creation of that token becomes possible, we outlaw such creation instead of picking a new token? So, pacific islanders should start massive projects to poison sea creatures with shells, to prevent the devaluation of a shell-based economy? And those people who use large carved stones for money, they should outlaw a hammer and chisel?

    From The Restaurant at the End of the Universe:

    "... Since we decided a few weeks ago to adopt the leaf as legal tender, we have, of course, all become immensely rich... But we have also run into a small inflation problem on account of the high level of leaf availability, which means that, I gather, the current going rate has something like three deciduous forests buying one ship's peanut... So in order to obviate this problem and effectively revalue the leaf, we are about to embark on a massive defoliation campaign, and ... er, burn down all the forests. I think you'll agree that's a sensible move under the circumstances."

  • According to one of my "Publication design" textbooks (the exact title escapes me), US Currency can be copied legally if it's black-and-white and reduced to smaller than 75% or enlarged to more than 125% of its actual size.

  • 1st: When you take a photocopy and photocopy it, the watermarks on the first one are usually lost, simply becuase the second copier often can't detect them.

    2nd: Watermarking is a benefit to individuals and freeware/copyleft/whatever. A number of free graphics (backgrounds, icons, etc.), including mine are deliberately watermarked. (In my case by hand). Almost every graphic has a small area that is a single color. For these areas, make a unique id in a different unused color and then change that color to have the same rgb as the surrounding areas. This way, if someone is using your work in a method you don't permit (aka, selling a quake mod using your graphics) you have a method of proving what was done. The same technique can be used with multiple colors if necessary. (The 1st 16 colors are only used in a "glider" [from the old game of life [nada.kth.se]] pattern. (16 colors allows you to repeat the pattern a LOT)

    There are ways to completely bollux the watermark. A simple soultion should be to laminate the copies. I doubt that the watermark could be properly read through the lamination and removing the lamination should ruin the copy effectively enough.

    Here's my question to slashdot: Do we find it offensive when companies copy the works of individuals and do we want methods to prevent this (for example Sun's actions with Blackdown's code)? If so, do we believe that corporations have the same rights to try to protect their works from individuals (recent articles on MP3 and DVD)? I almost wonder if we believe that the rights of "us" are more important than the rights of "them". - bonsai -

  • The critical difference between encoding a serial number and what we had with typewriters is this:

    Given a typewritten letter, and a typewriter, an expert can determine whether the letter was typed on that typewriter. Given a typewritten letter only, the expert can determine that the font is 120cpi courier.

    Given a photocopy with a serial number embedded in it, the manufacturer can determine that it's from a model number X4000, sold in Des Moines on June 17, 1999. If the user registered, or by consulting store receipts, you might be able to track this down to the person who made the copy.

    It's a difference between evidence that will actually let you track down the person you want, versus evidence that will let you demonstrate that the person you found is in fact the person you want.

    Given that any "crime" that this would be useful in, that is, any situation wherein someone wants to track someone down based on a piece of paper, has a very high likelihood of being an abuse of government power, or unrelated to any actual crime, is very high, and given that in a situation where a real crime has been committed (e.g. murder, as mentioned), the authorities will have other ways of tracking someone down, this is a very bad idea.

    I think that may be the longest sentence I have ever written.

  • if it's not open source you don't

    I wonder why nobody has challenged such information gathering under the laws covering unauthorized use of computers. To me this is no different from cracking a site and downloading something.

  • You know what? I am really beginning to see where the f1r5t p05t3rs are coming from. The moderation system is meant to keep people in line and contribute positively to the subject, but when a second post is marked redundant and a score of 1 is marked overated as has happened to my post you really begin to lose all respect for this thing called Karma. Mark me -5 if you want to I don't give a damn from now on I'm gonna say what the hell I want when the hell I want until the moderation system here improves. This past week I have been wrongly moderated a to a lose of over 10 karma, that is ridiculous I never intentially troll or insult anyone......until now.
  • You'd have to purchase that exact chip, read the information from the old PROM, change the serial number, write the new PROM, desolder the old chip, and solder in the new chip.

    Worse than that, unless you're only using the copier for "nefarious" purposes you'd probably have to solder in a socket instead so that you could alternate between the original chip (or a copy of it) and your hacked chip. After all, at some point there's a chance that an identifiable document from that machine will be scanned and the numbers correlated; if that happens at most company locations, when they ask "Well, who might know how to do this?" everyone will immediately think of one person. Even worse, some of these copiers may have a connector that techs use during maintenance to pull information - things like the ID, number of copies, error logs, all sorts of interesting* stats.

    So, the old chip has to be removed and read, a socket has to be mounted (using surface-mount tools that most people don't have available), new chips have to be burned, and it all has to be done without attracting attention by having the copier down for a significant amount of time so nobody calls in the techs. Oh, and that socket? Best make sure that board isn't something that gets looked at when the service guys are in, they might just notice something odd...

    Overall while it's probably possible to remove the serial number or corrupt it into unusability, it's probably not feasible to do so.

    * Well, to some people.

  • I believe the Soviet Union actually had a typewriter registry. And things like fax machines were strictly regulated.

    The Soviets went as far as to introduce their own incompatible video cassette recorder technology; this was done in the 1980s as a Glasnost-driven concession to consumer demand, whilst keeping Western media out of the public's hands. I believe it died pretty quickly.
  • by Nexeslad ( 106464 ) on Wednesday December 08, 1999 @02:59PM (#1474804)
    I have just found water marks on my toilet paper, should I be concerned?
  • by Jamie Zawinski ( 775 ) <jwz@jwz.org> on Wednesday December 08, 1999 @03:49PM (#1474819) Homepage

    The United States constitution does not specically grant a right to privacy. However, the supreme court has on many occasions upheld this as a basic American right. Many states constitutions specifically include such a right. California is one example.

    The Supreme Court has upheld privacy rights via the 4th Amendment: the idea is that there is a strong similarity between spying and search-and-seisure.

    However, contrary to popular belief, the Constitution does not enumerate the rights of the people. It enumerates the powers of the Government to restrict those rights. Rights belong to the people by default. I think most people have lost this key distinction. (I don't mean you.)

    This excellent article about the LAPD's extensive use of wiretapping [newtimesla.com] contains the following:

    The U.S. Supreme Court effectively outlawed wiretapping in 1967 by extending Fourth Amendment protections against unreasonable search and seizure to telephone conversations. But the following year, Congress decided to allow police interception of phone calls -- under strictly limited circumstances. Among them: that taps be authorized only by specified judges; that they be requested only by the highest ranking prosecutors; that they be employed only in investigating serious crimes; and, perhaps most importantly, that they be used only when other means of investigation had been exhausted or had proved useless.

    In other words, a wiretap could be used only as a tightly controlled method of last resort -- not as a broadly-cast net in a police fishing expedition.

    To insure taps were reasonably employed and to give their targets an opportunity to seek legal redress if they believed their privacy had been violated, Congress also insisted that law enforcement agencies fully disclose their use of taps, even when they didn't lead to arrests. But the federal guidelines were only minimum standards. "It's precisely because wiretaps represent such an invasion into people's privacy and their use is so potentially abusive," says Professor Pugsley, "that both federal and state laws are so stringent."

    Indeed, California's 1989 wiretap law put an even shorter leash on the snoopers than did Congress. The state law requires that all defendants be given transcripts of their recorded conversations. It also mandates that notice of the tap be promptly given to all persons whose voices are intercepted -- not just criminal suspects. And local prosecutors were ordered to provide the necessary information so that judges authorizing electronic surveillance could make that notification.

  • by Jamie Zawinski ( 775 ) <jwz@jwz.org> on Wednesday December 08, 1999 @03:51PM (#1474820) Homepage

    Canon color lasers (800, 1000, 2400, ect.) all have a board that recognizes things like money and postage stamps. If you try and copy any of these it will spit out all black copies, and will continue to do so until a Canon tech is called. (They usualy call the Secret Service)

    Do you have a reference for this?

    Good story, but since this is a Hard Problem, I'm skeptical, and I'm really curious how they do it if it is true.

  • You're missing the point. This is a copier serial number imbedded in the printed image. You can't filter it without rescanning it.

  • Not being interesting doesn't make it redudant dumbass, your IQ must be lower than my karma

    Come on moderate me down, I want ya too!

  • Yeah, not only do they consider the pen mightier than the sword but they consider the sword mightier than the gun. I can get arrested for walking down the street with a big ass sword in plain view but it is perfectly legal for me to carry a concealed pistol. Kinda ironic huh?

  • by quonsar ( 61695 ) on Wednesday December 08, 1999 @05:12PM (#1474832) Homepage
    Cash is intrinsically worthless, as it is a small piece of paper with a little bit of ink on it. The only reason it has value is because the government says it does.

    Slams at the government aside, I disagree. The only thing that makes ANYTHING valuable is agreement. A critical mass of human beings agree that cash is valuable, and so among human beings, it is. Give a $20 to your dog, he isn't impressed.

    Try to define 'value'. I am a real estate appraiser. How much is that property worth? How much money would a willing buyer agree to give and a willing seller agree to accept, each experiencing no undue influence, for the property? How does anybody determine this? By looking to see what other people have done with similar property, thats how. Do any of these people know anything, do they have some secret access to value knowledge? No. They simply agree, and they support that decision by referencing other agreements.

    A lot of people talk about the fact that paper money is no longer backed by precious metal. But so what? What makes the metal valuable? Agreement. How is that value affected by scarcity or abundance? Agreement. What caused the stock market crash of 1929 and the depression? Agreement. If a large enough mass of people no longer agree that what you have is valuable, then you are shit out of luck. Your stocks are worthless. Your money is worthless. A large enough mass of people agree that your bank is unsafe, it is.

    Its all agreement, its all very nebulous, and it could all come crashing down around us. All it would take is a little consensus.

    Rant concluded, plug commencing:
    Visit Sleepless in Seattle [meepzorp.com].

    "Rex unto my cleeb, and thou shalt have everlasting blort." - Zorp 3:16

  • by weave ( 48069 ) on Thursday December 09, 1999 @03:36AM (#1474895) Journal
    This is important folks. If a nation's currency is easily copied, then you'll have economic chaos, hyper inflation, and a host of other evils. Then all of a sudden you'll forget about a copier without watermarking. You'll be more worred about what it is you have of value that a person with extra food might want to trade you for.

    The Secret Service *has* to be serious about this.

    Someone also asked about why the US doesn't invalidate old bills. It's true. Most countries, when they introduce redesigned currency, set a date in the future when the old currency is no longer valid legal tender (except to collectors of course).

    The U.S. would never do this because the world views the dollar as "safe" and face it, there are a lot of people in foreign countries with trunks of hundred dollar bills (the old kind) stored. If they get an inkling that their stash will become worthless or greatly devalued, they'll be converting it to something else in short order.

    Yup, subversives and criminals are also important to the US economy. When they lose faith in the dollar, they'll sell dollars and buy currency from some other country leading to a weaker dollar.

    The dollar is the currency of the world, and I'm not just saying that because I am a US citizen. I grew up in the UK and generally hate US-centric attitudes, but this one is the truth.

Thus spake the master programmer: "When a program is being tested, it is too late to make design changes." -- Geoffrey James, "The Tao of Programming"